[Exim] internal error 421 ????

Morning everyone.

I have noticed a strange error in the log files:

2003-04-10 08:43:26 193Kg8-0000w8-00 == jennyw@???
<dns-admin@???> R=hub_route T=remote_smtp defer (0): SMTP error
from remote mailer after end of data: host 209.212.109.146
[209.212.109.146]: 421 Internal error. Connection closing
2003-04-10 08:43:26 193Kg8-0000w8-00 == waynel@???
<dns-admin@???> R=hub_route T=remote_smtp defer (0): SMTP error
from remote mailer after end of data: host 209.212.109.146
[209.212.109.146]: 421 Internal error. Connection closing
2003-04-10 08:43:26 193Kg8-0000w8-00 == jacquesv@???
<dns-admin@???> R=hub_route T=remote_smtp defer (0): SMTP error
from remote mailer after end of data: host 209.212.109.146
[209.212.109.146]: 421 Internal error. Connection closing
2003-04-10 08:43:26 193Kg8-0000w8-00 == support@???
<dns-admin@???> R=hub_route T=remote_smtp defer (0): SMTP error
from remote mailer after end of data: host 209.212.109.146
[209.212.109.146]: 421 Internal error. Connection closing
2003-04-10 08:43:26 193Kg8-0000w8-00 == thomask@???
<dns-admin@???> R=hub_route T=remote_smtp defer (0): SMTP error
from remote mailer after end of data: host 209.212.109.146
[209.212.109.146]: 421 Internal error. Connection closing

Any ideas how to fix this would be appreciated.

Thanks

Regards,

Tom Kinghorn